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    <title>Document</title>
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<body>
    <script>
        class Father {
            constructor(h, w) {
                this.h = h
                this.w = w
                console.log(11111111111)
            }
            static name = 'garvin'
            age = 11
            get fn() {
                return this.mut()
            }
            mut() {
                return this.h * this.w
            }
            muts() {
                return 3+8
            }

            static xx() {
                console.log(33333333333)
            }
        }
        const father = new Father(11, 9)
        Father.xx()
        class Son extends Father {
            constructor(name) {
                super()
                
                console.log("super",super.muts(),name)
            }
        }

       const son =  new Son('xx')
    </script>

    xxxxxxxxxxxxxxxxxxxx
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